High-voltage electric switch



J. G. ARMSTRONG HIGH-VOLTAGE ELECTRIC SWITCH 2 Sheets-Sheet INVENTOR;weed @ffm-6521 ci? BY Sept. 4, 1951 Filed March 16, 1950 Sept. 4, 1951J. G. ARMSTRONG 2,566,917

HIGH-VOLTAGE ELECTRIC SWITCH INVEN TOR.

Patented Sept. 4, 1951 HIGH-VOLTAGE ELECTRIC SWITCH James G. Armstrong,Centralia, Mo., assignor `to A. B. Chance Company, Centralia, Mo.,

poration of Missouri Application March 16, 1950, Serial No. 150,041

(Cl. ZOO-162) 4 Claims.

The present invention relates to high voltage electrical switches, andis particularly concerned with insulator supported electrical switcheswhich are adapted to be latched in the closed position, and manipulatedto open or closed position by a clamp stick.

One of the objects of the invention is the provision of an improvedswitch of the class described, the blade structure of which may bemanufactured more cheaply than the devices of the prior art, but at thesame time presents a more rigid and durable structure by virtue of itsimproved construction.

Another object of the invention is the provision of an improved switch,the switch arm of which is constructed out of tubular metal members, theends of which have been flattened to secure a maximum electrical contactwiththe terminals, and the intermediate parts of which are still in atubular shape and arranged in the manner of a truss for maximum lateralrigidity.

Another object of the invention is the provision of a switch of theclass described which is automatically latched when it moves to theclosed position, but which may be unlatched by apply- `ing a clamp stickto the operating ring and moving the ring in such a direction as to openthe switch, and which is also adapted to be supported in open position,where it is stopped automatically -by means of suitable stop elementscarried by the `switch arm and the pivot terminal.

Another object of the invention is the provision of an improved switchof the class described, which is durable, which has a minimum contactresistance, which may be manufactured economically, which is sturdy, andadapted to be used 4for a long period of `time without necessity forrepair or replacement of any of ,its parts.

lOther objects and advantages of the invention will be apparent from thefollowing description and the accompanying drawings, in which similar.characters of reference indicate similar lparts throughout the severalviews.

Referring to the drawings, of which there are two sheets,

Fig. 1 is a fragmentary side elevational view of .a high voltage switch`embodying my invention;

Fig. 2 isa top plan view omitting the electric insulators;

Fig. 3 is a fragmentary side elevational view in partial `section on theplane of the line 3-3 of Fig. 2, looking in the direction of the arrows,:showing the latching mechanism and the fixed terminal -of lthe switch;

Fig. -4 is a fragmentary sectional view, taken 2A on the plane of theline 4 4 of Fig. 3, looking in the direction of the arrows, and showingthe details of `construction at the latching end of the switch arm; I

Fig. 5 is a fragmentary elevational view in partial section, shown onthe plane of the line 5-.5 of Fig. 3, lookingin the direction of thearrows.

The present switch I0 is preferably insulator supported and may bemounted upon a pair of insulators I I and l2, which are carried by ametal frame member, such as a U-shaped channel (not shown. Theinsulators are of the type having metal members attached to their upperends, with threaded bores for receiving the screw bolts which secure theterminals to the insulators, such as, for example, the screw bolts I3 atthe right or pivot terminal and thescrew bolts I4 at the left orlatching terminal.

The pivoting terminal I5 may consist of a cast metal member providedwith a fiat base plate I6 of substantially the same shape as the top ofthe insulator and provided with bores for passing the screw bolts I'3,by means fof which it is secured to `the insulator. I

The base plate I5 hasan integral rearward extension Il, which isprovided with four threaded bores I8 for receiving the connector screwbolts I'il, by means of which a connector piate 2U is clamped to theextension I'l.V The line conductors are clamped in grooves in the platesIl and 20 by the screw bolts I9 threadedinto bores I8.

The terminal base I6 supports a pair of upwardly extendingpivot colums2|, 2|, each of which has a through 'bore 22 Y,for passing thescrewbolts .23. The screw bolts .23 also pass through bores 24 intheblades 25 and 26 0f the ,Switch arm 21.

Spring washers2B are included on ea-ch .of .the screw bolts 23 ,betweenthe head .and the blades `2li and 26; `and the spring washers arebrought inifo'resilient` and clamping engagement with the blades ,bytightening the nuts` 29.

Each .of .the pivot columns 2l has anouter plane surface 30 forengagement with the blades 25, 216. The blades 25er-1d L26 arepreferably made out 'of `.copper tubes by flattening the end portions3l., 32 adjacent the pivot terminal and by iiattening .the other endportions 33, 34 adjacent the fixed terminal 35.

Between the attened portions at 3l, 32 and 33, r3'II there aretheintermediate tubular por- .tions 36, 3J, which `merge into Vtheflattened por; tions at each lend by being gradually tapered i'nthickness and flattened The attened portions 33, 34 are .s0 bent thatthey fare parallel when 3 spaced sufficiently to engage the upwardlyextending legs 38, 39 of the xed terminal 35.

The other flattened ends 3| 32 are also bent so that they extendparallel when they engage the outer surfaces 3,0 of the terminal columns2|, which are spaced from each other as much as is permitted by thediameter of the base plate I6 at the pivot terminal. Thus the blades 25,26 of the switch arm 21 form a triangle and assume a truss-like shape,in which the tubular portions are placed, one under tension, and theother under compression by any lateral force, which tends to bend theswitch arm sidewise.

The xed terminal columns 2| may each be provided with a lower thickerportion 40, forming a horizontal stop shoulder 4|, which is locatedbelow each blade 3|, 32. The attened end portions 3|, 32 of each bladehave the straight end surfaces 42, which are located to come intoengagement with the shoulder 4| when the blade reaches the dotted lineopen position indicated at 43; and the lower rear corner 44v of eachflattened blade portion 3|, 32 is beveled closer to the spring washer 28than the location of the end 42, to clear the stop surface 4| as theblade pivots upward.

` Each pivot column 2| may be provided with an upward extension 45curved on the back side, but having an abrupt shoulder 46 on the frontside. This shoulder 46 is adapted to engage a transverse pin 41, whichpasses through apertures in each of the attened blade portions 3|, 32,and is secured at each end 48 by a through cotter pin.

The pin 41 engages the stop surface 46 at the same time that the stopsurface 42 engages stop 4|. The switches are customarily mounted invertical position, with the xed contact uppermost and the pivot columnlowermost. Thus the switch is held in open position by gravity.

At its other end the flattened portions 33, 34 are secured together inparallel position by a plurality of through rivets 49, which also passthrough a spacer block 50 engaging the inside of the blade portions 33,34. At its extreme end the flattened portions 33, 34 are securedtogether in parallel position by engaging a spacer block 5| (Fig. 4),which has a pair of through rivets 52 riveted over at both ends andclamping the blade portions to the block.

The spacer block 5| is provided with a round tapered socket 53 on itsinner side between the blades for receiving the compression spring 54,by means of which the latches 55 are urged toward the latching position55. The spring 54 has its other end mounted upon the cylindrical guideportion 56 of a spring supporting lever 51, which is provided with abearing ange 58 pivotally mounted upon a pintle 59 passing through bothof the depending latches 55.

Each of the latches comprises a metal member formed with a bearingportion 60 at the top and with a hook portion 6| at the bottom. The hookportion has a partially cylindrical recess 62 for `engaging a pin 63 andlatching the switch in closed position.

Each hook is also beveled at 64 on its lower side toward the pin 63 soythat when the switch is vpulled shut, the beveled portion 64 engagespin 63 to cam each latch to the open position until it passes over thepin and the pin 63 engages in the recess 62.

`The upper or bearing portion of each latch is pivotally mounted upon abolt 65 carried by the two flattened blade portions 33, 34 in throughapertures and provided with a cotter pin at its free end. The same bolt65 pivotally mounts a ring operating member 66 between the two latches Y55; and the ring operating member has a ilat body fitting between thelatches on the bolt 65.

The ring operator 66 also has a pair of depending flanges 61, one oneach side, engaging the right side of each latch 55 so that when thering operator is moved clockwise, the flanges 61 engage the latches 55and-move them to unlatching position against spring 54.

lThe body 68 of the ring operator '66 extends upward above the bladesand is provided with a ring 69 having a-round opening 10 suitable forengagement with a clamp Vstick or a disconnect stick of the `type havinga laterally extending lug and a head.

The body 68 has a laterally extending stop flange 1| on each side, whichprevents the ring operator 66 from moving counterclockwise any fartherthan the position of Fig. 3, where this ange 1| engages the top of eachblade. The flange 1| has another stop flange 12 extending upward andtoward the right in Fig. 3 at an obtuse angle for thepurpose of engagingthejtop edges of the blades on each side, when the ring operator ispivoted clockwise, to bring this ange into engagement with the blades. f

The body 68 of the ring operator 66 also has a prying extension 13located below the ange 12 and adapted to come into engagement with theflat end 14 of the terminal column 38 to pry the blades loose from theterminal 35 in the initial movement of the ring operator.

The other leg 39 of the terminal 35 may have a roundedend extendingabove the blades in Fig. 3. The xed terminal 35 of the switch comprisesa cast metal member having a base plate 15 provided with apertures forpassing the screw bolts |4, which are threaded into metal sockets thatare secured in the insulator.

The base plate 15 has a similar outward extension |3 supporting clampingplates |1 and 20, which are drawn together by the threaded bolts I8. Thebase plate 15 supports the upwardly extending terminal columns 38 and39, which are preferably rectangular in cross section and of suiiicientthickness to engage the inside of the flattened blade portions 33, 34tightly.

The terminal column 38 is provided with a laterally projecting verticalflange 16, which is adapted to go between the two latches 55, and whichcarries the latching pin 63 that serves as a keeper and projectslaterally from both sides of the iiange.

The two terminal columns 38, 39 are separated by a parallel sided slot11 of sufficient width to receive the tubular spacer 18, which iscarried'by a through bolt 19. The through bolt 19 passes throughregistering apertures in the flattened blade portions 33, 34, and isprovided on one end with a spiral compression spring 8l] compressedbetween the head 8| and the blade portion 33.

A spring washer 82 is compressed between the nut 83 on the threaded endof the bolt and the blade portion 34. The spacer 18 may be slightlyshorter than the thickness of the terminal columns 38, 39 so that thespring 80 and spring washer 82 press the blade portions 33, 34 intotight engagement with the terminal legs 38, 39. Y

The base plate 15 of terminal 35 is preferably provided with averticalilange 85 (Fig. 3) having a pair of bores for'receiving thescrewbolts 86 (Fig. 5), which are used with nuts to secure a U-shapedguideV member 81 to the baise.V U-shaped guide member has two upwardlyextending legs 88 and a lower yoke 89, the yoke TheV being provided withapertures for receiving the tous at.

The slot between the legs l88 is `indiiated at 590-; and -i-t is`rectangular iin sha-pe and bordered by laterally projecting ilanges'91, except 'tlataft 92 the reinforcing :flanges have outwardly flaringportions 93, `forming a diverg-ing mouth, which will engage the bladesvand guide them into en'- gagement with the legs 38, 39 ofthe fixedterminal 35.

The operation of lthe present switch is as follows: Assuming that "theswitch Vis closed, vas shown in Fig. 1, it may be 'opened Eby applying adisconnect stick to 'the Yring '6-9 fand pushing upward. This motionwill be resisted by the spring 54 because the `depending -ilange 'B1(Fig. 3) on the operator -65 engages the latches 55 and moves themclockwise 'to fthe unlatching position off the Spin 63. When the ring'has moved its extension 13 into engagement with the end 14 of theterminal prong `38, further movement of the operating ring 69 tends topry the blade off the terminal 35. A

The prying movement is required `only at the beginning of the motion ofthe switch arm because the moving friction is much less than the staticfriction. The prying continues until the flanges 12 engage the upperedges of the blade portions 33, 34. Thereafter the ring operator 5t canpivot no farther on the bolt A65 in a clockwise direction; and the ringoperator serves as a rigid handle for engagement with `the disconnect`stick to move the switch arm upward and to effect a disconnection atthe terminal 35.

The upward motion of the switch arm `may continue until it reaches thedotted line position, shown in Fig. 1, whereupon the pin 41 en gagesshoulder 46; and thejilat edge 42 engages shoulder il to prevent furtheropening motion of the switch ar'm.

` When the switch is to be closed, a disconnect stick may be employedagain in the 59, which is pulled downward. Any lateral component of thepull exerted is resisted by the trussu like structure of the switch arm21, the tubular portions 3S and 31 of which `are much stronger than theywould be if they were `flat.

As the switch arm approaches the terminal 35,

it is guided by the U-shaped guide member 81 into engagement with thelegs 38, 39. These terminal legs 38, 39 pass in between the flattenedportions 33, 34; and as the latches 55 approach the pin 53, the beveledsurface 64 on each latch cams the latches outward toward the left, untilthey pass over the pins 53 and snap into latching position. The switchis now closed and latched in closed position; and the parts are in theposition of Figs. 1 and 3.

It will thus be observed that I have invented .l

an improved high voltage switch, the switch arm of which is of astructure like a truss and having two tubular side members, which arespread at one end and brought together at the other end. Flattening thetubular members at the ends gives them both an extended plane contactarea for engaging the terminals, which reduces contact resistance.

The tubular members are secured together at both ends, and areresiliently clamped to the pivot terminal so that the friction issuflicient to hold the switch in open position against gravity. At theother end the terminal has a guide for guiding the switch arm intoengagement with the terminal, and is provided with an automatic latchiorlll'a'tching the. `switch in `closed position `and for prying theswitch to open position.

While vl have illustrated a :preferred 'em'bozdiment `of my invention,manymodincations may be made without 'departing from the spirit of the`in;- vention, and I do not wish to be limited to the precise 'details`vor construction set forth, but desire to avail myself vof vall changeswithin the scopelof the appended claims.

Having thus 'described my invention, what `I claim as new and `desire tosecure by Letters Paitent 'of Vthe United States, is:

1. In a high voltage switch, the combination oi a support with a .pairof insulators, each 'of said insulators having a metal cap provided withthreaded bores, a fixed contact terminal carried by the cap of oneinsulator, a pivot `terminal litting carried by the other insulator andsecured thereto by threaded members, said pivot terminal having a pairof upwardly extending spaced parallel pivot columns, and a movableswitch arm pivotally mounted on said columns, said switch arm.comprising a pair of blade members, the said blade `members eachcomprising a tubular metal member having both of its ends flattened toprovide inner plane contacting surfaces, the tubular portionsintermediate the ends extending di agonall'y 'outward toward the pvotterminal columns, and the flattened end portions adjacent said columnsbeing pivotally mounted on said columns -by clamping screw bolts, 4eachscrew bolt having a spring washer for resiliently pressing theiiatten'ed portions against the pivot columns to reduce contactresistance, the said pivot columns being provided on their upper endswith upwardly extending shoulders, and the blades being provided withaligned apertures adjacent said col'-` umns and with a through stop pinin said apertures and located to engage said upwardly rex@r tendingshoulders when the arm is opened and moved to an upwardly extendingposition.

2. In a high voltage switch, the combination of a support with a pair ofinsulators, each of said insulators having a metal ca'p provided withthreaded bores, a fixed contact terminal carried by the cap 'of oneinsulator, a pivot terminal fitting carried by the other insulator andsecured thereto by threaded members, said pivot terminal having a pairof upwardly extending spaced parallel pivot columns, and a movableswitch arm pivotally mounted on said columns, said switch arm comprisinga pair of blade members, the said blade members each comprising atubular metal member having both oi its ends flattened to provide innerplane contacting surfaces, the tubular portions intermediate the endsextending diagonally outward toward the pivot terminal columns, and theflattened end portions adjacent said columns being pivotally mounted onsaid columns by clamping screw bolts, each screw bolt having a springwasher forresilientlypressing the flattened portions against the pivotcolumnsto reduce contact resistance, the said pivot columns beingprovided on their upper ends with upwardly extending shoulders, and theblades being provided with aligned apertures adjacent said columns andwith a through stop pin in said apertures and located to engage saidupwardly extending shoulders when the arm is opened and moved to anupwardly extending position, said xed contact terminal comprising asupporting base and a pair of longitudinally spaced upwardly extendingprongs separated by a slot, said prongs being of slightly greater widththan the spacing between 7 the adjacent attened end portions of theswitch blades.

3. In a high voltage switch, the combination of a support with a pair ofinsulators, each of said insulators having a metal cap provided withthreaded bores, a xed contact terminal carried Vby the cap of oneinsulator, a pivot terminal fitting carried by the other insulator andsecured thereto by threaded members, said pivot terminal having a pairof upwardly extending spaced parallel pivot columns, and a movableswitch arm pivotally mounted on said columns, said switch arm comprisinga pairof blade members, the said blade members each comprising a tubularmetal member having both of its ends flattened to provide inner planecontacting surfaces, the tubular portions intermediate the endsextending diagonally outward toward the pivot terminal colu umns, andthe flattened end portions adjacent said columns being pivotally mountedon said columns by clamping screw bolts, each screw bolt having a springwasher for resiliently pressing the flattened portions against the pivotcolumns to reduce contact resistance, the said pivot columns beingprovided on their upper ends with upwardly extending shoulders, and theblades being provided with aligned apertures adjacent said columns andwith a through stop pin in said apertures and located to engage saidupwardly extending shoulders when the arm is opened and moved to anupwardly extending position, said fixed contact terminal comprising asupporting base and a pair of longitudinally spaced upwardly extendingprongs separated by a slot, said prongs being of slightly greater widththan the spacing between the adjacent attened end portions of the switchblades, the switch blades being provided with a pair of elongatedattened portions arranged on opposite sides of said prongs and spacedfrom each other in parallel relation by a tubular spacer and a throughsecuring member at each end of said latter flattened portions.

4. In a high voltage switch, the combination of a support with a pair ofinsulators, each of said insulators having aY metal cap provided withthreaded bores, a fixed contact terminal carried by the cap of oneinsulator, a pivot terminal ntting carried by the other insulator andsecured thereto by threaded members, said pivot terminal having a pairof upwardly extending spaced parallel pivot columns, and a movableswitch arm pivotally mounted on said columns, said switch CJI armcomprising a pair of blade members, the said blade members eachcomprising a tubular metal member having both of its ends attened toprovide inner plane contacting surfaces, the tubular portionsintermediate the ends extending diagonally outward toward the pivotterminal columns, and the atttened end portions adjacent said columnsbeing pivotally mounted on said columns by clamping screw bolts, eachscrew bolt having a spring washer for resiliently pressing the iiattenedportions against the pivot columns to reduce contact resistance, thesaid pivot columns being provided on their upper ends with upwardlyextending shoulders, and the blades being provided with alignedapertures adjacent said columns andY with a through stop pin in saidapertures and located to engage said upwardly extending shoulders whenthe arm is opened and moved to an upwardly extending position, said xedcontact terminal comprising a supporting base and a pair oflongitudinally spaced upwardly extending prongs separated by a slot,said prongs being of slightly greater Width than the spacing between theadjacent flattened end portions of the switch blades, the switch bladesbeingv provided with a pair of elongated attened portions arranged onopposite sides of said prongs and spaced from each other in parallelrelation by a tubular spacer and a through securing member at each endof said latter attened portions, and said parallel flattened portionsbeing traversed at the slot between said prongs by a transverselyextending bolt provided with a threaded securing member, and havingspring means on said bolt outside of each flattened portion to press theflattened portions together against the prongs and to permit theirseparation suiciently to receive the prongs.

JAMES G. ARMSTRONG.

REFERENCES CITED I The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

